Coffee mill



June 10 1924. 1,496,823

c. M. N'Evws COFFEE MILL Filed on. a. 1923 lmvenmr;

Patented June 10, 1924.

UNITED STATES CONDICT M. NEVIUS, OF HORNELL, NEW YORK.

COFFEE MILL.

Application filed October 8, 1923. Serial No. 667,213.

T 0 aZZ whom it may concern.

Be it known that I, CoNoIoT M. NEviUs, a citizen of the United States, residing at Hornell, in the county of Steuben and State of New York, have invented certain new and useful Improvements in Oolfee Mills; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to coffee-mills of the type in which a mass of coffee is given a whirling motion within a cylinder, provided with a series of cutting blades adjacent to slots through which the ground coffee escapes. In such machines it has been proposed to regulate the fineness, to which the coffee is ground, by adjusting the effective width of the slots through which it escapes.

In Letters Patent of the United States No. 1,459,790, dated June 26, 1923, I have disclosed a machine of the type in question, in which two concentric slotted cylinders are used, the outer cylinder being provided with integrally-formed cutting-blades, and the inner cylinder constituting a guardcylinder to control the effective width of the slots. tion is to simplify and improve the construction in question, while also increasing the efliciency of the machine. that this may be accomplished by reversing the relative position of the two cylinders and by changing the shape of the slots in the cutter-cylinder in such a way as to facilitate the access of the coffee-grains to the cutting-edges.

Another feature of the invention resides in simple and effective means for producing and controlling the relative rotation of the cylinders, through which the effective width of the slots is adjusted.

In the accompanying drawings Fig. 1 is a side-elevation, partly in section, of a coffee-mill embodying the present invention; and Fig. 2 is a section on the line 22 in Fig. 1.

The invention is illustrated as embodied in a mill in which the whirling motion is imparted to the coffee by a rotary impeller comprising a series of arms 5 grojectin in ovlindrica relation, from a isc 6. his 15a is fixed on a ower shaft 7, which may conveniently be t e armature shaft of an The object of the present inven-.

I have found electric motor, one end of the casing 8 of such motor being shown in Fig. 1.

The coffee is introduced into the space within the arms 5 through a curved passage 9, which is fed in the usual manner by a hopper 81.

The cutter-cylinder 10 is closely embraced by the guard-cylinder 11. The cutter-cylinder is stationary, being fixed by an end-flange 12 which is screwed to the housing of the mill. It is centered by a flange 13 projecting inwardly on the housing. The guard-cylinder is rotatable upon the cuttercylinder, for the purpose of adjustment, and is provided at one end with a rin 14 to which the adjusting-means are attac ed.

As shown in Fig. 2, both cylinders are provided with cooperatin slots, and a fea ture of the invention resi es in the form of the slots in the cutter-cylinder. Each of these slots has, at one side, an edge forming substantially a right-angle with the inner surface of the cylinder, while the opposite edge is beveled at a very obtuse angle. The square edge, 15, constitutes the cutting-edge, since the impeller is rotated in the direction, as indicated by the arrow in Fig. 2, to throw th coffee against this edge. The beveled edge has the function of permitting the coffee both to enter and to leave freely the space adjacent the cutting-edge.

In the fine grinding or pulverizing of cofi'ee in a mill of the type in question, it has been found that the best results are secured by using a cutter having a relatively obtuse or blunt edge such as the square edge 15 herein illustrated. Where the operation of the mill is regulated by a simple guard-cylinder as herein. shown, this cylinder does not cooperate with the cuttercylinder to control directly the size of the particles cut from the coffee-beans, but it acts merely to control the escape of cut particles from the zone of action. When a coffeebean is thrown forcibly against the cutter-blade it is more or less crushed, with the formation of particles of various sizes.

Such of these particles as are of the desired degree of fineness may escape at once through the slot adjacent the blade, but the coarser particles must be returned to the space within the cutter-cylinder, so as to continue their whirling motion and be brought again into enga 'elnent with a e11t= terblade. I have foun that this action results most efi'ectively where the slots in the L rec-ydknl are (of fiornl .desci-i in fh ,case .eaeh siiiehslot constitutes, in effect, a shallow widely-open pocket into which particles thrown by centrifugal force, and out of which the coarser particles may be again impeled by impingement of the stream of fol owing particles.

The slots 17 in the guard-cylinder may be ofazyy form which .wilil not tend to cause jamming oithe growled material,

For the purpose of adjusting the guardeyl snder, the housing 5E8 of the mill is 7 r0- vided with .an upper extension i19 -wlziic is bored to receive a short roclhshwfit 20. "fiShisroek-shaift is boned Leqoentfiieally to re eeime 'i loose pivot-pin 21, and em] of the lpin :ifs gorked to en e the end of an arm 92. This arm is lined rhlizafl ly in the mg 14 on the LQILCl of the gmra xi linder. M1 as 23, fixed in the rear end of the tdcksheft, egitends thnough 3am a'rcuateslot in a mange on the housing, and a nut 25, threaded on the outer end of the arm 23, engages s washer 26 which seats upon the periphery of the flimge. By swinging the a-i m =251 he roar-shaft may :be turned, which q'esufi t s, an 'oloifiious manner, in a slight par tlia l rotation of guard-cylinder upon the cutteheylinder, and the parts may then he {firiotiox'ialfly secured in adjusted position 'by llig hteming the innit against the washer Q6,

"The fc li'sc G'carrie's two fan-blades '27 which oree-te a ailment or an- Within 'the e sin 'hy hilji fil' i the groi-ind materia l is entrained find is carr ed to the discharge-spout -28.

The i'pvmien is mt limited to the em-- bodime'nt herein described sfnd illustrated,

but it may be 'e'rribodie'd in vgi'rio s other forms within the scope of the tolowing claims. i '"The invent" n claimed is:

'1. Infl/Eo ee-mill, in combination with a rotary impeller, two concentric slotted cylindex-s, each slot in (the sinn r r 11 =0utter- @Wflifldfir :heing substantially square at one side, to form a cutting-edge, and inwardly bevelled at the opposite side to promote access of the coffee to the cutting-edge.

2. A coffee-mill, as defined in claim 1, provided further with means for producing a partial relative rotation of the two cylinders to adjust the extent of overlap of their slots.

3. 'In a cofi'ee-mill, in combination with a rotary impeller, a stationany cutter-cylinder provided with poekets, in its inner 511115568, each having two inwardly-divergent 'ivatklsy one of said walls forming 2J1 obtuse angle with {the inner surface of the cylinder and the other ifiorming substantially a right-angile therewith; said pockets beingiofgemter width than depth, and the cutter-cylinder being provided, at the bottom of leach pocket, with a relatively narrow sldt for the escaipe oi' the grou-amlmateriel.

4. A cofieertm'ill, as defined in claim 1'3, provided further with means for adjusting! the effective width .of said slots.

5. in a oolhee-mill comprising a cuttercylinder and a concentric igzuand cyl'inde r, means for relatively adjusting the cylinders by artial rotation, comprising an arm lire-q 'jecting radially from one cylinder; a rockshaft; a pin eccenti ida'lly mounted in the rodk-shafit and connected to said arm and means foiroeking the rock-shiafit and for se'ci'iringit inad jns ted posit-ion comprising '80 1a "second arm projecting from the rook-shaft and screw fihi'eaded, an arcuate stationery member with a, slot in which said second arm may swing, and a mrt threaded on said arm and adaflted to apply frictional pres- '65 sure against [the periphery of the stationary member to secure the partsin adjusted position.

ooNnIoT M, NEVws. 

